A liquid crystal panel is being widely used for a display section of a display device. The liquid crystal panel cannot emit light by itself, and thus uses light of a lighting device (so-called, backlight device) to display an image. This type of lighting device is arranged on a rear surface side of the liquid crystal panel and is configured to irradiate the rear surface of the liquid crystal panel with light spread to a planar form.
A lighting device including a light guide plate, and an LED (Light Emitting Diode) light source arranged to oppose an end face of the light guide plate is known for the lighting device. This type of lighting device is generally referred to as an edge light type (or side light type) and is known to be a device suited for thinning, power saving, and the like.
In the edge light type lighting device, the end face of the light guide plate becomes a light entering surface, to which light from the LED light source enters, and a plate surface on a front side of the light guide plate becomes a light exiting surface, through which light entering through the light entering surface exits toward the liquid crystal panel. The light guided from the light entering surface into the light guide plate is propagated through the light guide plate while repeating reflection and the like, and exits through the light exiting surface.
In recent years, a display device having a wide variety of shapes is being demanded due to diversification in design and application of the display device. For example, Patent Document 1 illustrates a configuration in which an electronic equipment including the display device is applied to a meter unit arranged on an instrumental panel of an automobile. The display device has a through-hole formed in the lighting device (light guide plate thereof) and includes a cap inserted to the through hole. The document describes that the cap is preferably formed with a non-light transmissive resin to suppress light leakage.